There has recently been a remarkable advance in technology regarding compression of music data, moving image data, or the like (hereinafter, referred to as contents data) and an achievement of a large capacity of a compact hard disk or a flash memory. This advance has also brought about development of a contents data reproducing apparatus which selects, among a great volume of contents data recorded in the hard disk or the flash memory, necessary data to be reproduced. The hard disk or the flash memory has features that the amount of data to be recorded is much greater compared with other recording media such as a cassette, an MD, and a CD, and that high-speed random access is allowed to arbitrary data. Utilizing those features, for example, a music data reproducing apparatus such as a stationary music player or portable music player, or a car audio having a function of shuffle reproduction (random reproduction) of music data or programmed reproduction in which a reproducing order of music data is specified, has come into wide use.